javascript实现国密sm4算法(支持微信小程序)

概述：

本人前端需要实现sm4计算的功能，最好是能做到分多次计算。
本文所写的代码在现有sm4的C++代码，反复测试对比计算过程参数，成功改造成sm4的javascript代码，并成功验证好分多次计算sm4数据

测试平台：

已经在如下环境中测试通过，其他平台(浏览器)应该也不会有问题：
1、nodejs中node.exe运行
本js脚本按照版本ES5编写代码，当然微信小程序也能用。

功能代码:

javascript">function strSm4CtxParams() {
  this.sk;
};

var FK = [0xa3b1bac6,0x56aa3350,0x677d9197,0xb27022dc];
var CK =  [  
	0x00070e15,0x1c232a31,0x383f464d,0x545b6269,  
	0x70777e85,0x8c939aa1,0xa8afb6bd,0xc4cbd2d9,  
	0xe0e7eef5,0xfc030a11,0x181f262d,0x343b4249,  
	0x50575e65,0x6c737a81,0x888f969d,0xa4abb2b9,  
	0xc0c7ced5,0xdce3eaf1,0xf8ff060d,0x141b2229,  
	0x30373e45,0x4c535a61,0x686f767d,0x848b9299,  
	0xa0a7aeb5,0xbcc3cad1,0xd8dfe6ed,0xf4fb0209,  
	0x10171e25,0x2c333a41,0x484f565d,0x646b7279  
]; 

var SboxTable = [  
	0xd6,0x90,0xe9,0xfe,0xcc,0xe1,0x3d,0xb7,0x16,0xb6,0x14,0xc2,0x28,0xfb,0x2c,0x05,  
	0x2b,0x67,0x9a,0x76,0x2a,0xbe,0x04,0xc3,0xaa,0x44,0x13,0x26,0x49,0x86,0x06,0x99,  
	0x9c,0x42,0x50,0xf4,0x91,0xef,0x98,0x7a,0x33,0x54,0x0b,0x43,0xed,0xcf,0xac,0x62,  
	0xe4,0xb3,0x1c,0xa9,0xc9,0x08,0xe8,0x95,0x80,0xdf,0x94,0xfa,0x75,0x8f,0x3f,0xa6,  
	0x47,0x07,0xa7,0xfc,0xf3,0x73,0x17,0xba,0x83,0x59,0x3c,0x19,0xe6,0x85,0x4f,0xa8,  
	0x68,0x6b,0x81,0xb2,0x71,0x64,0xda,0x8b,0xf8,0xeb,0x0f,0x4b,0x70,0x56,0x9d,0x35,  
	0x1e,0x24,0x0e,0x5e,0x63,0x58,0xd1,0xa2,0x25,0x22,0x7c,0x3b,0x01,0x21,0x78,0x87,  
	0xd4,0x00,0x46,0x57,0x9f,0xd3,0x27,0x52,0x4c,0x36,0x02,0xe7,0xa0,0xc4,0xc8,0x9e,  
	0xea,0xbf,0x8a,0xd2,0x40,0xc7,0x38,0xb5,0xa3,0xf7,0xf2,0xce,0xf9,0x61,0x15,0xa1,  
	0xe0,0xae,0x5d,0xa4,0x9b,0x34,0x1a,0x55,0xad,0x93,0x32,0x30,0xf5,0x8c,0xb1,0xe3,  
	0x1d,0xf6,0xe2,0x2e,0x82,0x66,0xca,0x60,0xc0,0x29,0x23,0xab,0x0d,0x53,0x4e,0x6f,  
	0xd5,0xdb,0x37,0x45,0xde,0xfd,0x8e,0x2f,0x03,0xff,0x6a,0x72,0x6d,0x6c,0x5b,0x51,  
	0x8d,0x1b,0xaf,0x92,0xbb,0xdd,0xbc,0x7f,0x11,0xd9,0x5c,0x41,0x1f,0x10,0x5a,0xd8,  
	0x0a,0xc1,0x31,0x88,0xa5,0xcd,0x7b,0xbd,0x2d,0x74,0xd0,0x12,0xb8,0xe5,0xb4,0xb0,  
	0x89,0x69,0x97,0x4a,0x0c,0x96,0x77,0x7e,0x65,0xb9,0xf1,0x09,0xc5,0x6e,0xc6,0x84,  
	0x18,0xf0,0x7d,0xec,0x3a,0xdc,0x4d,0x20,0x79,0xee,0x5f,0x3e,0xd7,0xcb,0x39,0x48  
];  

function sm4_init(keyArray, isToEncrypt) {
	var sm4CtxParams = new strSm4CtxParams();
	var i = 0;
	var tmpInt = 0;
	
	sm4CtxParams.sk = new Array(32);
	
	Setkey(sm4CtxParams, keyArray);
	
	if (isToEncrypt == false) {
		for (i = 0; i < 16; i++) {
			tmpInt = sm4CtxParams.sk[i];
			sm4CtxParams.sk[i] = sm4CtxParams.sk[31 - i];
			sm4CtxParams.sk[31 - i] = tmpInt;
		}
	}
	
	//for (i = 0; i < 32; i++) {
	//	console.log("%dsk=%d", i, sm4CtxParams.sk[i]);
	//}
	return sm4CtxParams;
}

function sm4_encrypt(sm4CtxParams, byteArrayDataIn) {
	return sm4_crypt_round(sm4CtxParams, byteArrayDataIn);
}

function sm4_decrypt(sm4CtxParams, byteArrayDataIn) {
	return sm4_crypt_round(sm4CtxParams, byteArrayDataIn);
}

function sm4_crypt_round(sm4CtxParams, byteArrayDataIn) {
	//unsigned long i = 0;  
	//unsigned long ulbuf[36]; 
	var i = 0;	
	var ulbuf = new Array(36);
	var output = new Uint8Array(16);

	//memset(ulbuf, 0, sizeof(ulbuf)); 
	for (i = 0; i < ulbuf.length; i++) {
		ulbuf[i] = 0;
	}
	
	GET_ULONG_BE( ulbuf, 0, byteArrayDataIn, 0 );  
	GET_ULONG_BE( ulbuf, 1, byteArrayDataIn, 4 );  
	GET_ULONG_BE( ulbuf, 2, byteArrayDataIn, 8 );  
	GET_ULONG_BE( ulbuf, 3, byteArrayDataIn, 12 );  
	i = 0;
	while(i<32) {  
		ulbuf[i+4] = F(ulbuf[i], ulbuf[i+1], ulbuf[i+2], ulbuf[i+3], sm4CtxParams.sk[i]);  
		i++;  
	}  
	PUT_ULONG_BE(ulbuf, 35, output, 0);  
	PUT_ULONG_BE(ulbuf, 34, output, 4);  
	PUT_ULONG_BE(ulbuf, 33, output, 8);  
	PUT_ULONG_BE(ulbuf, 32, output, 12); 
	
	return output;
}

function GET_ULONG_BE(n, nindex, b,i) {                                                       
	n[nindex] = ( (parseInt(b[(i)    ]) & 0xff) << 24 )        
	| ( (parseInt(b[(i) + 1]) & 0xff) << 16 )        
	| ( (parseInt(b[(i) + 2]) & 0xff) <<  8 )        
	| ( (parseInt(b[(i) + 3]) & 0xff)       );       
}

function PUT_ULONG_BE(n, nindex, b,i){
	(b)[(i)    ] = ( (n[nindex]) >> 24 ) & 0xff;       
	(b)[(i) + 1] = ( (n[nindex]) >> 16 ) & 0xff;       
	(b)[(i) + 2] = ( (n[nindex]) >>  8 ) & 0xff;       
	(b)[(i) + 3] = ( (n[nindex])       ) & 0xff;       
} 

function SHL(x,n) {
	return (((x) & 0xFFFFFFFF) << (n%32));
}

function ROTL(x,n) {
	return (SHL((x),(n)) | ((x) >>> (32 - ((n)%32))));
}

function Lt(ka) {  
	//unsigned long bb = 0;  
	//unsigned long c = 0;  
	//unsigned char a[4];  
	//unsigned char b[4];  
	var a = new Uint8Array(4);
	var b = new Uint8Array(4);
	var tmpInt = new Array(1);
	var bb = 0;
	
	tmpInt[0] = ka;
	PUT_ULONG_BE(tmpInt,0,a,0);  
	ka = tmpInt[0];
	
	b[0] = Sbox(a[0]);  
	b[1] = Sbox(a[1]);  
	b[2] = Sbox(a[2]);  
	b[3] = Sbox(a[3]); 
	
	tmpInt[0] = bb;
	GET_ULONG_BE(tmpInt,0,b,0); 
	bb = tmpInt[0];
	
	return bb^(ROTL(bb, 2))^(ROTL(bb, 10))^(ROTL(bb, 18))^(ROTL(bb, 24));  
	//return c;  
}  

function F(x0, x1, x2, x3, rk) {  
	return (x0^Lt(x1^x2^x3^rk));  
} 

function Sbox(inch)  
{  
	//unsigned char *pTable = (unsigned char*)SboxTable;  
	//unsigned char retVal = (unsigned char)(pTable[inch]);  

	//return retVal;  
	return SboxTable[inch];
}  

function CalciRK(ka) {  
	//unsigned long bb = 0;  
	//unsigned long rk = 0;  
	//unsigned char a[4];  
	//unsigned char b[4];
	var bb = 0;
	var rk = 0;
	var a = new Uint8Array(4);
	var b = new Uint8Array(4);
	var tmpInt = new Array(1);
	
	tmpInt[0] = ka;
	PUT_ULONG_BE(tmpInt, 0, a, 0);  
	ka = tmpInt[0];
	
	//console.log("ka = %d a = %d %d %d %d", ka, a[0], a[1], a[2], a[3]);
	
	b[0] = Sbox(a[0]);  
	b[1] = Sbox(a[1]);  
	b[2] = Sbox(a[2]);  
	b[3] = Sbox(a[3]); 
	
	tmpInt[0] = bb;	
	GET_ULONG_BE(tmpInt, 0, b, 0); 
	bb = tmpInt[0];
	
	rk = bb^(ROTL(bb, 13))^(ROTL(bb, 23));
	//console.log("rk = %d", rk);
	return rk;  
}

function Setkey(sm4CtxParams, key) {  
	//unsigned long MK[4];  
	//unsigned long k[36];  
	//unsigned long i = 0;  
	var i = 0;
	var MK = new Array(4);
	var k = new Array(36);

	GET_ULONG_BE(MK, 0, key, 0 );  
	GET_ULONG_BE(MK, 1, key, 4 );  
	GET_ULONG_BE(MK, 2, key, 8 );  
	GET_ULONG_BE(MK, 3, key, 12 );  
	//console.log("mk = %d %d %d %d", MK[0], MK[1], MK[2], MK[3]);
	k[0] = MK[0]^FK[0];  
	k[1] = MK[1]^FK[1];  
	k[2] = MK[2]^FK[2];  
	k[3] = MK[3]^FK[3];  
	//console.log("k = %d %d %d %d", k[0], k[1], k[2], k[3]);
	for(; i<32; i++) {  
		k[i+4] = k[i] ^ (CalciRK(k[i+1]^k[i+2]^k[i+3]^CK[i]));  
		sm4CtxParams.sk[i] = k[i+4];  
		//console.log("sk%d=%d", i, sm4CtxParams.sk[i]);
		//return;
	}  
}  


function sm4_str_to_array(strIn) {
  var bytesArray = new Uint8Array(strIn.length);
  var i = 0;

  for (i = 0; i < strIn.length; i++) {
    bytesArray[i] = strIn.charCodeAt(i);
  }

  return bytesArray;
}

function sm4_hex_to_array(hexStrIn) {
  var i = 0;
  var cnt = 0;
  var ele = 0;
  var bytesArray = null;

  cnt = 0;
  for (i = 0; i < hexStrIn.length; i++) {
    ele = hexStrIn.charCodeAt(i);
    if (ele >= 48 && ele < 48 + 10) {
      cnt++;
    }
    if (ele >= 65 && ele < 65 + 6) {
      cnt++;
    }
    if (ele >= 97 && ele < 97 + 6) {
      cnt++;
    }
  }
  bytesArray = new Uint8Array(parseInt((cnt + 1) / 2));
  cnt = 0;
  for (i = 0; i < hexStrIn.length; i++) {
    ele = hexStrIn.charCodeAt(i);
    if (ele >= 48 && ele < 48 + 10) {
      ele -= 48;
      cnt++;
    } else if (ele >= 65 && ele < 65 + 6) {
      ele = ele - 65 + 10;
      cnt++;
    } else if (ele >= 97 && ele < 97 + 6) {
      ele = ele - 97 + 10;
      cnt++;
    } else {
      continue;
    }
    if ((cnt % 2) == 1) {
      bytesArray[parseInt((cnt - 1) / 2)] = (ele << 4) & 0xF0;
    } else {
      bytesArray[parseInt((cnt - 1) / 2)] |= ele;
    }
  }

  return bytesArray;
}

function sm4_hex_to_str(data, len) {
  var hex_digits = "0123456789abcdef";
  var output = new String();
  var i = 0;

  for (i = 0; i < len; i++) {
    output += hex_digits.charAt((data[i] >>> 4) & 0x0f);
    output += hex_digits.charAt((data[i]) & 0x0f);
  }

  return output;
}

测试代码：

javascript">var sm4Ctx = null;
var result = null;
var result2 = null;

sm4Ctx = sm4_init(sm4_hex_to_array("00112233445566778888888800000000"), true);
result = sm4_encrypt(sm4Ctx, sm4_hex_to_array("1234567890ABCDEF0000007788552233"));
console.log("sm4 encrypt:" + sm4_hex_to_str(result, 16));

sm4Ctx = sm4_init(sm4_hex_to_array("00112233445566778888888800000000"), false);
result2 = sm4_decrypt(sm4Ctx, result);
console.log("sm4 decrypt:" + sm4_hex_to_str(result2, 16));